Question

in a two digit number, the ten's digit is three times the unit digit. when the number is decreased by 54, the digits are reversed. find the number.

Answer 1

Let the digit at unit's place be x.
GIVEN : digit at Ten’s place = 3x
Number formed :
10 × 3x + x = 30x + x = 31x
Number formed after reversing the digits:
10 × x + 3(x )= 10x +3x = 13x
ATQ,
31x -54 = 13x [Given]
31x -13x = 54
18x = 54
x = 54/18
x= 3
Number = 31x = 31 × 3 = 93
Hence, the number is 93.

HOPE THIS WILL HELP YOU...

Answer 2

Hi Mate !!

Let the Unit digit be x
and tens digit be y


Original number :- 10y + x
Reversed number :- 10x + y

• the ten's digit is three times the unit digit.

y = 3x ........ ( i )


• when the number is decreased by 54, the digits are reversed.

10y + x - 54 = 10x + y

10y - y + x - 10x = 54

9y - 9x = 54

9 ( y - x ) = 54

y - x = 54/9

y - x = 6 ..... ( ii )


Putting value of y from ( i ) in ( ii )

y - x = 6

3x - x = 6

2x = 6

x = 6/2

x = 3

Putting value of x in ( i )

y = 3x

y = 3 × 3

y = 9


The required number is 10y + x :- 93